It's possible that there is no dual channel, so the laptop would not take a performance hit due to mismatched sticks.
I can not tell the configuration of the slots from their specs page [0].
Their configuration page [1] confirms that it's 8GB+32GB to get the 40GB.
Why wouldn't they just offer 2x16GB to get the dual-channel memory? Unless, of course, the laptop does not support dual-channel memory...
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